Apparatus for delivery of reinforcing materials to bone

ABSTRACT

An apparatus and methods for delivery of reinforcing materials to a weakened or fractured bone is disclosed. An apparatus for delivering a reinforcing mixture to a bone including a tube having a proximal end, a distal end, and a longitudinal axis therebetween, wherein the tube has at least one inner lumen capable of allowing a bone reinforcing mixture to pass therethrough; a balloon engaging the tube wherein the balloon expands from a substantially deflated state to a substantially inflated state upon the bone reinforcing mixture entering the balloon; and at least one light guide extending through the tube into the balloon to guide a light into the balloon.

RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.14/164,846, filed Jan. 27, 2014, which is a continuation of U.S. patentapplication Ser. No. 13/561,249, filed Jul. 30, 2012, now U.S. Pat. No.8,668,701, which is a continuation of U.S. patent application Ser. No.12/875,460, filed Sep. 3, 2010, now U.S. Pat. No. 8,246,628, which is acontinuation of U.S. patent application Ser. No. 11/789,907, filed Apr.26, 2007, now U.S. Pat. No. 7,806,900, which claims the benefit of U.S.Provisional Application Ser. No. 60/795,626, filed Apr. 26, 2006, U.S.Provisional Application Ser. No. 60/858,202, filed Nov. 10, 2006, andU.S. Provisional Application Ser. No. 60/880,646, filed Jan. 16, 2007,and the entirety of all these applications are hereby incorporatedherein by reference for the teachings therein.

FIELD

The embodiments disclosed herein relate to bone strengthening andreinforcing, and more particularly to apparatus and methods for deliveryof reinforcing materials to a weakened or fractured bone.

BACKGROUND

Bone is a living tissue and plays a structural role in the body. Boneconsists of repeating Harvesian systems (concentric layers of lamellaedeposited around a central canal containing blood vessels and nerves).The central canal is also known as the medullary cavity and is filledwith bone marrow. Within the shaft of a long bone, many of theseHarvesian systems are bundled together in parallel, forming a kind ofbone called compact bone, which is optimized to handle compressive andbending forces. In some bones, such as the metacarpals, the bonesthemselves are hollow and contain little, if any, marrow. Near the endsof the bones, where the stresses become more complex, the Harvesiansystems splay out and branch to form a meshwork of cancellous or spongybone. Compact bone and cancellous bone differ in density, or how tightlythe tissue is packed together.

Collagen rods support the bone and are surrounded by minerals (includingcalcium and phosphorus) from the blood that crystallize and surround thecollagen rods. These minerals give the bones strength while the collagenrods provide resiliency.

Genetic or developmental irregularities, trauma, chronic stress, tumors,and disease can result in pathologies of bones. Some bone diseases thatweaken the bones include, but are not limited to, osteoporosis,achondroplasia, bone cancer, fibrodysplasia ossificans progressiva,fibrous dysplasia, legg calve perthes disease, myeloma, osteogenesisimperfecta, osteomyelitis, osteopenia, osteoporosis, Paget's disease,and scoliosis. Weakened bones are more susceptible to fracture, andtreatment to prevent bone fractures becomes important. Severe fractures,such as those that are open, multiple, or to the hip or back, aretreated in a hospital. Surgery may be necessary when a fracture is open,severe, or has resulted in severe injury to the surrounding tissues.Severe fractures may require internal devices, such as screws, rods, orplates to hold the bone in place or replace lost bone during the healingprocess.

In many cases where the bone has fractured, a bone cement mixture, or abone void filler, is added into the bone to repair and strengthen thebone. Prior art bone cement mixtures are typically two part (powder andliquid), require a catalyst, and are exothermic. Injection devices areused to inject bone cement into bone. A typical bone cement injectiondevice has a pistol-shaped body, which supports a cartridge containingbone cement where the injection device is usually a high pressuredelivery source. More specifically, a trigger actuates a spring-loadedor screw ram, which forces a volume of bone cement in a viscouscondition through a suitable nozzle and into the interior of a bonetargeted for treatment. The amount of bone cement mixture injected is afunction of the amount of space within the bone structure and theability to reach the open areas in the bone. In some cases, the presenceof bone marrow restricts the amount of bone cement mixture that can beused.

In thermal characterization tests of polymethylmethacrylate (PMMA) bonecement performed according to the ASTM Standard Specification forAcrylic Bone Cement, time and temperature profiles of bone cement wereobserved to be sensitive to the thickness of the cement patty and themold material. Due to the heat transfer from the cement to thesurrounding mold, such tests might underestimate the exothermictemperature of bone cement. That is, the mold material and geometry mayinfluence the values of the parameters measured.

Bone cements may be difficult to work with and cause complications.Leakage of bone cements can result in soft tissue damage as well asnerve root pain and compression. Other complications associated with theuse of bone cements for vertebroplasty and kyphoplasty procedures mayinclude pulmonary embolism, respiratory and cardiac failure, abdominalintrusions, ileus, and death.

Prior art techniques for adding a bone cement mixture to repair orstrengthen bone are described in U.S. Pat. No. 4,969,888 entitled“Surgical Protocol for Fixation of Osteoporotic Bone Using InflatableDevice,” U.S. Pat. No. 5,108,404 entitled “Surgical Protocol forFixation of Osteoporotic Bone Using Inflatable Device,” U.S. Pat. No.5,824,087 entitled “Bone Regeneration,” U.S. Pat. No. 6,241,734 entitled“Systems and Methods for Placing Materials Into Bone,” U.S. Pat. No.6,395,007 entitled “Apparatus and Method for Fixation of OsteoporoticBone,” U.S. Pat. No. 6,425,923 entitled “Contourable Polymer FilledImplant,” U.S. Pat. No. 6,887,246 entitled “Apparatus and Method forFixation of Osteoporotic Bone,” U.S. Pat. No. 6,875,212 entitled“Curable media for implantable medical device,” U.S. Pat. No. 6,964,667entitled “Formed in place fixation system with thermal acceleration,”U.S. Publication No. 2004/0225296 entitled “Devices and methods using anexpandable body with internal restraint for compressing cancellousbone,” and U.S. Publication No. 2005/0142315 entitled “Liquidperfluoropolymers and medical applications incorporating same.”

The prior art injection devices are typically invasive and havedifficulty quickly terminating the flow of cement should the cavity fillbefore the spring-actuated load cycle is completed. Conventional cementinjection devices also have difficulty adjusting or controlling theinjection volume or injection rate in real time in reaction tocancellous bone volume and density conditions encountered inside thebone.

Thus, there is a need in the art for apparatuses and methods fordelivering reinforcing materials into a bone using minimally invasivetechniques, with ease of use, greater rate and volume control, and afaster response time.

SUMMARY

Systems and methods for reinforcing weakened or fractured bone aredisclosed herein. According to aspects illustrated herein, there isprovided an apparatus for delivering a reinforcing mixture to a boneincluding a tube having a proximal end, a distal end, and a longitudinalaxis therebetween, wherein the tube has at least one inner lumen capableof allowing a bone reinforcing mixture to pass therethrough; a balloonengaging the tube wherein the balloon expands from a substantiallydeflated state to a substantially inflated state upon the bonereinforcing mixture entering the balloon; and at least one light guideextending through the tube into the balloon to guide a light into theballoon.

According to aspects illustrated herein, there is provided an apparatusfor delivering a reinforcing mixture to a bone including a catheterhaving a proximal end, a distal end, and a longitudinal axistherebetween, wherein the catheter has at least one inner lumen capableof allowing a bone reinforcing mixture to pass therethrough; a balloonextending from the catheter wherein the balloon begins to expand from asubstantially deflated state to a substantially inflated state as thebone reinforcing mixture enters the balloon; and a junction connectingthe catheter to the balloon, wherein the junction concentrates stressapplied to the catheter at the junction.

According to aspects illustrated herein, there is provided a method forreinforcing a bone including penetrating the bone to gain access to acavity in the bone; inserting a balloon catheter into the cavity in thebone; infusing a bone reinforcing mixture into a balloon of the ballooncatheter through at least one lumen of a catheter; and activating alight source to harden the bone reinforcing mixture in the balloon.

According to aspects illustrated herein, there is provided a method forreinforcing a bone including penetrating the bone to gain access to acavity in the bone; inserting a balloon into the cavity in the bone;infusing a bone reinforcing mixture into the balloon through at leastone lumen of a catheter connected to the balloon; and separating thecatheter from the balloon at a predetermined site.

Various embodiments provide certain advantages. Not all embodiments ofthe invention share the same advantages and those that do may not sharethem under all circumstances. Further features and advantages of theembodiments, as well as the structure of various embodiments aredescribed in detail below with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The presently disclosed embodiments will be further explained withreference to the attached drawings, wherein like structures are referredto by like numerals throughout the several views. The drawings shown arenot necessarily to scale, with emphasis instead generally being placedupon illustrating the principles of the presently disclosed embodiments.

FIG. 1 shows a perspective view of an illustrative embodiment of acatheter having a balloon in an inflated state;

FIG. 2 shows a cross-sectional view of an illustrative embodiment of aballoon in a bone;

FIG. 3 shows a cross-sectional view of an illustrative embodiment of acatheter;

FIG. 4 shows a cross-sectional view of the catheter taken along line 4-4of FIG. 3;

FIG. 5 shows a cross-sectional view of an illustrative embodiment of acatheter;

FIG. 6 shows a cross-sectional view of an illustrative embodiment of acatheter having an optical taper;

FIG. 7 shows a cross-sectional view of an illustrative embodiment of acatheter having an optical taper;

FIG. 8 shows a cross-sectional view of an illustrative embodiment of anillumination band area of a catheter;

FIG. 9 shows a cross-sectional view of an illustrative embodiment of aswitch for an illumination band area of a catheter;

FIG. 10 shows a cross-sectional view of an illustrative embodiment of aswitch for an illumination band area of a catheter;

FIG. 11 shows a cross-sectional view of an illustrative embodiment of aballoon catheter;

FIG. 12 shows a cross-sectional view of an illustrative embodiment of aballoon catheter in a deflated state;

FIG. 13 shows a cross-sectional view of an illustrative embodiment of aballoon catheter in an inflated state;

FIG. 14 shows a cross-sectional view of an illustrative embodiment of afractured bone with a guidewire therein;

FIG. 15 shows a cross-sectional view of an illustrative embodiment of abone and a guidewire with a balloon catheter inserted on the guidewire;

FIG. 16 shows a cross-sectional view of an illustrative embodiment of abone, a guidewire and a balloon catheter in an inflated state;

FIG. 17 shows a cross-sectional view of an illustrative embodiment of afractured bone;

FIG. 18 shows a cross-sectional view of an illustrative embodiment of aballoon catheter inserted in a fractured bone;

FIG. 19 shows a cross-sectional view of an illustrative embodiment aballoon catheter in an inflated state in a bone;

FIG. 20 shows a cross-sectional view of an illustrative embodiment of aballoon in a deflated state in a fractured bone;

FIG. 21 shows a cross-sectional view of an illustrative embodiment of aballoon in an inflated state in a fractured bone;

FIG. 22 shows a cross-sectional view of an illustrative embodiment of aballoon;

FIG. 23 shows a cross-sectional view of an illustrative embodiment of aballoon in a bone;

FIG. 24 shows a cross-sectional view of an illustrative embodiment of aninternal support structure of a balloon;

FIG. 25 shows a cross-sectional view of an illustrative embodiment of astent in a contracted state;

FIG. 26 shows a cross-sectional view of an illustrative embodiment of astent in an expanded state;

FIG. 27 shows a cross-sectional view of an illustrative embodiment ofconnector wires and Nitinol plates;

FIG. 28 shows a perspective view of an illustrative embodiment ofNitinol and hinge wires;

FIG. 29 shows a perspective view of an illustrative embodiment of aplate; and

FIG. 30 shows a perspective view of an illustrative embodiment of aframe.

While the above-identified drawings set forth presently disclosedembodiments, other embodiments are also contemplated, as noted in thediscussion. This disclosure presents illustrative embodiments by way ofrepresentation and not limitation. Numerous other modifications andembodiments can be devised by those skilled in the art which fall withinthe scope and spirit of the principles of the presently disclosedembodiments.

DETAILED DESCRIPTION

Apparatuses and methods for the controlled delivery of reinforcingmaterials to weakened or fractured bones are disclosed herein. Anapparatus and methods for the inflation of a balloon within the lumen ofa bone to reduce a fracture is disclosed herein. Apparatus and methodsdisclosed herein may be performed in a sterile environment.

Reinforcing materials include, but are not limited to, bone reinforcingmixtures (such as bone cement mixtures, bone void fillers, epoxies,glues and similar adhesives), orthopedic wires, stainless-steel rods,metal pins, and other similar devices. An apparatus may be used for therepair of bones that have weakened or fractured due to any of the bonediseases including, but not limited to osteoporosis, achondroplasia,bone cancer, fibrodysplasia ossificans progressiva, fibrous dysplasia,legg calve perthes disease, myeloma, osteogenesis imperfecta,osteomyelitis, osteopenia, osteoporosis, Paget's disease, scoliosis, andother similar diseases.

Embodiments of the apparatus may be used for delivering reinforcingmaterials to a bone void that has been prepared in a bone using, forexample, the disclosed techniques. Although some of the figures show theweakened or fractured bone as a femur, those skilled in the art willrecognize that the disclosed apparatus and methods can be used fordelivering reinforcing materials to other bones, such as the tibia,fibula, humerus, ulna, radius, metatarsals, metacarpals, phalanx,phalanges, ribs, spine, vertebrae, clavicle and other bones and still bewithin the scope and spirit of the disclosed embodiments.

As shown in FIG. 1 and FIG. 3, a flexible tube is a catheter 100 havingan elongated shaft with a proximal end 102, a distal end 104, and alongitudinal axis therebetween. The distal end 104 of the catheter 100has a balloon portion 106 that inflates and deflates. In an embodiment,the balloon 106 may be round, flat, cylindrical, oval, rectangular oranother shape. In an embodiment, a glue 108, such as UV-activated glue,is used to inflate and deflate the balloon 106. A separation area 109 islocated at the junction between the balloon 106 and the catheter 100.The separation area 109 may also be an illumination band 110. Whenactivated, the illumination band 110 causes light to cure glue 108located in the catheter within the illumination band 110, as will bedescribed further below. The illumination band 110 may include lightguides 112 which transmit light of the proper frequency to theillumination band 110.

As shown in the embodiment depicted in FIG. 4, the catheter 100 includesa catheter wall 114, illumination fibers 116, an illumination ring 118for holding together the illumination fibers 116, and an inner lumen 120through which the glue 108 is introduced. In an embodiment, it may bedesirable for the balloon to separate from the catheter, allowing theballoon to remain in the bone and the catheter to be more easilyremoved. For example, as shown in the embodiment depicted in FIG. 5, thecatheter 100 includes two fused joints 122 and a pre-stressed notch 124which facilitate a separation of the balloon 106 from the catheter 100,as will be described further below.

The balloon portion of the catheter may be located and inflated at anylocation along the length of the catheter. The catheter may engage thetubular balloon in such a way as to allow for an open communicationchannel. The ability to inflate and deflate the balloon ensures thatalignment of the plurality of bone fragments for proper healing prior tocuring the glue. In an embodiment, inflation of the balloon within theinner lumen of the bone conforms to the shape of the inner bone surface,leading to greater contact area, and provides a custom fit. Thoseskilled in the art will recognize that a balloon can be formed of apliable, resilient, conformable, and strong material, including but notlimited to urethane, polyethylene terephthalate, nylon elastomer andother similar polymers.

In an embodiment, a catheter may be constructed in a “Y” shape havingtwo arms extending from a longer base. The longer base of the Y shapedcatheter is inserted into the bone. A first upper arm of the Y shapeengages a syringe. A second upper arm of the Y shape engages a lightsource. An optical taper may be used and is located between the lightsource and the catheter. In an embodiment, an outside circumference ofthe catheter ranges from about 3 French to about 8 French. Using acatheter of about 3 French to about 8 French, results in an inflateddiameter of the balloon of about 2 mm to about 30 mm inflated diameter,as appropriate for the internal lumen of the bone. Not all embodimentsare intended to be limited in this respect and some embodiments mayinclude a catheter having an outside circumference of less than 3 Frenchor greater than 8 French.

In an embodiment, the catheter can be constructed of illuminationmaterials resulting in a light transmittable fiber catheter, which wouldnot require illumination fibers or light guides.

In an embodiment, an elongated flexible tube having at least one lumen,capable of receiving a fluid from both ends, extends through a flexiblebone fitting portion. The flexible tube may also be screwed into a bonevia a screw-thread portion. In an embodiment, the elongated flexibletube is a thin catheter. In an embodiment, the elongated flexible tubeis a balloon catheter.

The infusion catheter connects the light guides to the light source andprecludes inadvertent or early activation of the light source (e.g.,prior to the correct positioning and desired infusion amount of UVcurable glue). The activation of the light source cures the glueresulting in the affixing of the balloon in the expanded shape. A curemay refer to any chemical, physical, and/or mechanical transformationthat allows a composition to progress from a form (e.g., flowable form)that allows it to be delivered through the catheter, into a morepermanent (e.g., cured) form for final use in vivo. For example,“curable” can refer to uncured composition, having the potential to becured in vivo (as by catalysis or the application of a suitable energysource), as well as to a composition in the process of curing (e.g., acomposition formed at the time of delivery by the concurrent mixing of aplurality of composition components). The activation of the light sourcethat is connected to the light guides within the balloon causes acomplete cure of the reinforcing material to the point where thecomposition has been finally shaped for its intended use. Activation ofthe glue does not require a change in shape post activation; there isnot shrinking or swelling of the glue after curing.

Once the balloon catheter is positioned, the balloon can be inflated ordeflated until the bone is brought to a proper orientation. The balloonis expanded from a deflated state to an inflated state using a UV curedepoxy where a syringe of UV curable epoxy is attached to the luer end ofthe catheter. The balloon is considered to be in an inflated state whenthe balloon has a greater volume than when the balloon was in a deflatedstate. The balloon need not be maximally inflated for the balloon to beconsidered to be in an inflated state. The balloon withstands highpressure during and after inflation. Inflatable non-conforming balloonsare typically capable of withstanding about 400 PSI to about 1000 PSIfilled with a UV curable material. The UV curable material becomes arigid orthopedic fixator capable of holding bone in approximation toeffect healing. When the balloon is subjected to internal pressures, theballoon inflates into a cross-sectional shape, which can be circular,oval, disk or similar shapes. The balloon material is flexible, butrelatively inelastic so there is minimal radial expansion upon theinflation beyond the pre-defined shape.

In an embodiment, the balloon is designed to evenly contact the wall ofthe cavity in the bone. For example, as depicted in the embodiment ofFIG. 2, the pre-defined shape of a balloon 220 may be an elongatedcylinder. The balloon 220 has two ends 222, 224 and a surface 226therebetween. The surface 226 of the balloon 220 is substantially evenand/or smooth and substantially mates with a wall 228 of a cavity 230 inthe bone. The balloon's surface 226 may not be entirely smooth and mayhave some small bumps or convexity/concavity along its length. In someembodiments, there are no major protuberances jutting out from thesurface 226 of the balloon 220. The balloon may be designed to remainwithin the cavity of the bone and not protrude through any holes orcracks in the bone. In an embodiment, the balloon's outer surface may beflush with the wall of the cavity and when the balloon is inflated, theballoon's outer surface may contact the wall of the cavity along atleast a portion of the balloon's surface area. In an embodiment, whenthe balloon is inflated, a majority or all of the balloon's outersurface does not contact the wall of the cavity and does not extendthrough any holes or cracks in the bone.

In an embodiment, the balloon may be contoured to fit inside a cavity ina particularly shaped bone. The balloon may be shaped to fit inside aparticularly shaped cavity in a bone. In an embodiment, the balloon maybe shaped to fit entirely within the cavity of the bone and not protrudeout of the cavity through any holes or cracks in the wall of the cavityof the bone.

Upon inflation to higher internal pressures, the balloon assumes anormal cross section. The balloon shape is suitable for balloons formedof polyethylene terephthalate (PET) and similar materials which are notreadily heat settable. In an embodiment, the inflation of the balloonwithin an inner lumen of the bone provides for an even dispersion ofradial force. Some balloons may be capable of withstanding more thanabout 1000 PSI or less than about 400 PSI, as not all embodiments areintended to be limited in that respect.

In an embodiment, the balloon has a diameter of about 5 mm and a lengthof about 55 mm±4 mm. The length of the balloon may be approximately 44mm±3.5 mm, 30 mm±3 mm or any other length greater than, equal to or lessthan about 55 mm, about 40 mm, or about 30 mm and may have any othermargin of error, and the diameter of the balloon may be any size, as notall of the present embodiments are intended to be limited in theserespects.

The balloon catheter includes a plurality of inner delivery lumensextending outward through a sidewall of the balloon portion and endingin a plurality of passageways that act as delivery surfaces for thedelivery of the bone reinforcing mixture. The plurality of passagewaysmay reside anywhere along the length of the balloon portion of theballoon catheter, for example, along the entire length of the balloonportion. The distal end of the balloon catheter may include a radiopaquemarker, band, or tip which ensure easy visualization by fluoroscopyduring catheter manipulation. The proximal end of the flexible tube maybe attached to any adhesive system known in the art to which the bonereinforcing mixture has been placed. Examples of adhesive systemsinclude, but are not limited to, caulking gun type systems, syringesystems, bag systems that contain the bone reinforcing material wherethe delivery of the bone reinforcing material is controlled using a tubeclamp or any other restrictor valve.

The balloon catheter includes a light source path, such as a fiber, thatruns down the length of the catheter, either inside the lumen, or on theoutside of the catheter, and is able to cure the bone reinforcingmixture once it has been released from the plurality of passageways.When the reinforcing material in the balloon catheter is cured using alight source, light is delivered to cause the glue to cure. Curing aballoon catheter using a light source path uses curing compounds whichremain stable until activated by light. The compounds do not require anyweighing or mixing prior to application. In operation, radiant energyfrom a UV light source may be absorbed and converted to chemical energyquickly so that curing happens almost instantaneously. Since curingoccurs immediately upon light striking the curing compounds, anysubstrates will not experience a temperature change or only a brief,superficial temperature change and reaction is not consideredexothermic.

In an embodiment, a syringe has a control mechanism to regulate the flowof the glue. The control mechanism of the syringe allows the glue toflow into the catheter and can stop the flow if desired. The syringemakes direct contact to control the directional flow of the glue, andthe direction of flow of the glue instantaneously changes within thecatheter in response to a change in the direction of the syringe.

In an embodiment, the delivery syringe does not allow light to penetratethe outer surface of the syringe. Having an opaque syringe ensures thatthe reinforcing material contained in the syringe is not exposed tolight and will not cure in the syringe. The delivery syringe delivers anepoxy or glue to the balloon through the catheter. The epoxy is of aliquid consistency, as measured in Centipoise (cP), the unit of dynamicviscosity, so the epoxy can be infused from the syringe into thecatheter and into the balloon. Because the epoxy has a liquidconsistency and is viscous, the epoxy can be delivered using lowpressure delivery and high pressure delivery is not required, but may beused.

After activating the light source, the light is delivered throughout theepoxy in the balloon. By activating the light source, the photocurablematerial contained in the balloon hardens inside the balloon.

The bone reinforcing mixture may be a natural or synthetic material forstrengthening, replacing, or reinforcing of bones or bone tissue. Bonereinforcing mixtures include glues, adhesives, cements, hard tissuereplacement polymers, natural coral, hydroxyapatite, beta-tricalciumphosphate, and various other biomaterials known in the art forstrengthening, replacing or reinforcing bones. As inert materials, bonereinforcing mixtures can be incorporated into surrounding tissue orgradually replaced by original tissue. Those skilled in the art willrecognize that numerous bone reinforcing mixtures known in the art arewithin the spirit and scope of the presently disclosed embodiments.

The electromagnetic spectrum is the range of all possibleelectromagnetic radiation. The electromagnetic spectrum of an object isthe frequency range of electromagnetic radiation that it emits,reflects, or transmits. The electromagnetic spectrum extends from justbelow the frequencies used for modern radio (at the long-wavelength end)to gamma radiation (at the short-wavelength end), covering wavelengthsfrom thousands of kilometers down to fractions of the size of an atom.Ultraviolet (UV) light wavelength ranges from about 1 nm to about 380nm, and can be subdivided into the following categories: near UV(380-200 nm wavelength; abbreviated NUV), far or vacuum UV (200-10 nm;abbreviated FUV or VUV), and extreme UV (1-31 nm; abbreviated EUV orXUV). Similarly, visible light has a wavelength spectrum of betweenabout 380 to about 780 nm.

Light Cured Materials (LCMs) utilize energy provided by ultraviolet (UV)or visible light. Being very energetic, UV light can break chemicalbonds, making molecules unusually reactive or ionizing them, in generalchanging their mutual behavior. In an embodiment, a light emitted by alight source reacts with a photoinitiator sensitive to UV light orvisible light. Photoinitiators provide important curing mechanisms foraddition polymerization.

Using a UV light, the reinforcing material ensures there is no orminimal thermal egress and that the thermal egress may not be long induration. More specifically, there is no chemical composition or mixingof materials. The introduction of light starts the photoinitiator andthe glue hardens. Once the light is introduced, the material inside theballoon hardens and the materials inside are affixed in place. Until thelight is introduced, the bone placement is not disturbed or rushed asthere is no hardening of a glue until the light is introduced, theballoon may be inflated or deflated due to the viscosity of the glue.The glue may be infused or removed from the balloon due to the lowviscosity of the material. In an embodiment, the viscosity of thereinforcing material is less than approximately 1000 cP. Not allembodiments are intended to be limited in this respect and someembodiments may include reinforcing materials having a viscosity exactlyequal to or greater than 1000 cP.

Different light cured materials use photoinitiators sensitive todifferent ranges of UV and visible light. For example, visible bluelight may be useful to the curing process as it allows materials to becured between substrates that block UV light but transmit visible light(e.g., plastics). Visible light increases the cure speed of light curedmaterials since a greater portion of the electromagnetic spectrum isavailable as useful energy. Further, visible light penetrates throughlight cured materials to a greater depth-enhancing cure depth. The lightcured materials cure in such a way that is sufficient to hold a bone inthe correct orientation. More specifically, the ability to inflate, set,adjust, orient bones, and the resulting union of the bone are availableprior to hardening the glue. Examples of light cured materials includethose commercially available from Loctite of Henkel Corporation, locatedin Rocky Hill, Conn.

In an embodiment, a liquid adhesive such as a cationic epoxy having acationic photoinitiator is used. A pre-activated epoxy exhibits a verylow shrink rate. To activate, a UV light in about 245 nm to about 365 nmrange is applied to an epoxy and starts a cure reaction. Once the curereaction is started, that reaction continues to completion (e.g., evenin the dark).

In an embodiment, the reinforcing material is a bioabsorbable epoxy sothe hardened epoxy is absorbed into the body over time. In anembodiment, the reinforcing material is cured by chemical activation orthermal activation. Chemical activation includes but is limited to wateror other liquids. In an embodiment, the reinforcing material is a dryingadhesive which has a polymer dissolved in a solvent such that as thesolvent evaporates, the adhesive hardens. In an embodiment, thereinforcing material is a hot or thermoplastic adhesive such that as theadhesive cools, the adhesive hardens. The reinforcing material is notlimited to the embodiments described herein and may be any material thatreinforces the bone. Some materials may require or be enhanced by curingvia any means, such as UV or visible light, heat, and/or addition orremoval of a chemical or substance, may utilize any outside or internalprocesses to cure the material, or may not require curing.

In an embodiment, the bone reinforcing mixture is a light cure adhesive(or UV adhesive). A benefit of ultraviolet (UV) curing is that it is acure-on-demand process and that adhesives may be free of solvents andinclude environmentally friendly resins that cure in seconds uponexposure to long wave UV light or visible light. In an embodiment, theUV adhesive is a single-component, solvent-free adhesive that will notcure until a UV light engages the adhesive, and when that occurs, theadhesive will cure in seconds to form a complete bond with a shearstrength. Visible light penetrates through the epoxy to a greater depth.Since the visible light penetrates through the epoxy, curing of thematerial increases as a greater portion of the electromagnetic spectrumis available as useful energy. In this way, light cured materialsutilize energy provided by ultraviolet light or visible light to start acuring process. Light emitted by a source reacts with a photoinitiatorsensitive to UV light or to visible light. Visible light allowsmaterials to be cured between substrates that block UV light buttransmits visible light. Using the UV light to cure the reinforcingmaterial assists in holding broken bones in place, filling of theballoon, and viewing under a C arm imaging system.

Those skilled in the art will recognize that some light cured materialsmay be activated by UV light, visible light, x-rays, gamma rays,microwaves, radio waves, long waves or any light having a wavelengthless than about 1 nm, between about 1 nm and about 380 nm, between about380 nm and about 780 nm, or greater than 780 nm, as not all embodimentsare intended to be limited in that respect.

Several epoxies known in the art are suitable for use as bonereinforcing materials and vary in viscosity, cure times, and hardness(durometer or shore) when fully cured. A durometer of a materialindicates the hardness of the material, defined as the material'sresistance to permanent indentation. Depending on the amount ofresultant support that is necessary for a given bone fracture, aspecific durometer UV adhesive may be chosen. Alternately, multiple UVadhesives having varying durometers may be chosen for the repair of abone fracture and be within the scope and spirit of the presentlydisclosed embodiments. The durometer of a material may be altered toachieve either greater rigidity or a more malleable result. As shown inFIG. 24, the shore or durometer of the epoxies may also be varied in alayer-by-layer approach to achieve a softer more malleable outer layeror a rigid internal structure. The shore or durometer may also bealtered to ensure the interface between the glue and the bone isflexible similar to natural shock absorption.

The mechanical properties of the epoxies may dictate usingmethods/measures that are typical for high-strength and high-impactmaterials including but not limited to, tensile strength and tensilemodulus, tensile strength tests, ultimate modulus, Poisson's ratio,hardness measurements like Vickers and Charpy Impact which measuresyield strength and toughness.

In an embodiment, the epoxy has an elastic modulus of about 0.1 to about50 GPa, preferably about 1 to about 10 GPa. Cranial-facial bones have anelastic modulus of about 20 GPa, while plexiglass (PMMA, i.e. bonecement) has an elastic modulus of about 1 to about 2 GPa. Typicalepoxies have an elastic modulus in the range of about 1 to about 3 GPa,but nano-modified epoxies can have about a 3-5 fold or more increaseover the original epoxy with only a few percent loading of carbonnanotubes, clay, mica, and other structures.

In an embodiment, carbon nanotubes (CNTs) are added to the reinforcingmaterial to increase the strength of the glue. Carbon nanotubes are anallotrope of carbon that take the form of cylindrical carbon moleculesand have novel strength properties. Carbon nanotubes exhibitextraordinary strength. Nanotubes are members of the fullerenestructural family, which also includes buckyballs. Whereas buckyballsare spherical in shape, a nanotube is cylindrical with at least one endtypically capped with a hemisphere of the buckyball structure. Nanotubesare composed entirely of sp2 bonds, similar to those of graphite. Thisbonding structure, which is stronger than the sp3 bonds found indiamond, provides the molecules with their unique strength. Nanotubesnaturally align themselves into “ropes” held together by Van der Waalsforces. Single walled nanotubes or multi-walled nanotubes may be used tostrengthen the reinforcing materials.

In an embodiment, glue is infused through a lumen in the catheter toexpand the balloon to position the bone in a healing orientation. Toestablish the healing orientation, the balloon inflates until the bonesmove into an aligned orientation. Orientation of the bones may be donewithout any visualization of the process or using x-ray or afluoroscope. A C arm imaging system is a fluoroscope that may allowmovement or manipulation of the fluoroscope to rotate around tissuewhile viewing. Other techniques can be used for monitoring or inspectingthe delivery or use of the balloon such as magnetic resonance imaging(MRI), ultrasound imaging, x-ray fluoroscopy, Fourier transform infraredspectroscopy, ultraviolet or visible spectroscopy. The balloon iscomposed of non ferromagnetic materials and, thus, is compatible withMRI.

Once the glue is hardened, the glue has the appropriate tensilestrength, yield, elongation, and other properties to ensure a goodbonding of the bone-to-bone repair and maintain strength for healingbone for at least about six weeks. An intramedullary pin or rod iscreated to hold the bone in a proper healing orientation. Theimplantable intramedullary rod or pin is capable of being inserted intothe bone without driving or insertion force. In an embodiment, the gluemixture has a viscosity of about cP 1000 or less. A contrast materialcould be added to the glue mixture without significantly increasing theviscosity. Contrast material including, but not limited to, bariumsulfate, tantalum, or other contrast materials known in the art. In thisway, the glue mixture may be used with a smaller lumen during delivery.

Many glues have a specific cure time dependant upon time and temperatureafter which the glue enters the plastic region. The disclosed glues cureinstantaneously upon activation of a light source allowing a desiredamount of glue in a precise location that can cure once struck byincident light.

In an embodiment, a plurality of light guides engage the light source.In an embodiment, the light guide is a flexible light pipe. The lightguide directs light from a light source to the balloon catheter. Becausethe light source is larger than the diameter of the catheter, a lighttaper is used to direct the light. As shown in the embodiments depictedin FIG. 6 and FIG. 7, an optical taper 146 may be used for focusing thelight from a light source into a smaller catheter 135. In an embodiment,the optical taper 146 is a shaped bundle of optical fibers 116 having alight source that is concentrated at a proximal end 148. As shown in theembodiment of FIG. 7, the catheter also includes a taper holder 137, alight shield 139, a fiber boss 141, a handle 143, illumination bundles145 having diameters, for example, of about 0.5 mm, about 0.75 mm, about1.0 mm, about 1.25 mm and/or about 1.5 mm, and a polyimide sheathing147.

In an embodiment, an optical taper is a single or “multi-element” rod ofoptical fibers. When a single or multi-element rod is tapered, theresulting optical characteristic of the rod changes to reduce theNumerical Aperture (NA) of the normal end, while maintaining theoriginal Numerical Aperture at the tapered end. The Numerical Apertureof an optical system is a dimensionless number that characterizes therange of angles over which the system can accept or emit light. Theamount of change is a ratio of the diameters. When light enters thesmall end of a taper at a full acceptance angle, the emerging beam atthe other end may be collimated as compared to the original range ofentry angles. In an embodiment, a catheter has an interface with anoptical taper. In an embodiment, the optical taper engages the catheterand is for a single use and disposable. In an embodiment, the opticaltaper engages the light source and may be used for multiple procedures.

In an embodiment, using an optical taper shapes a concentration of alight beam at the proximal end of the catheter. A disposable section ofcatheter fibers may be aligned to the taper to improve quality. Anoptical taper also may provide an appropriate mating point for adisposable piece. One advantage of using an optical taper is that thedesign of a catheter is simpler because small optical fibers are alignedunder a larger optical taper. Since the small optical fibers are alignedunder a larger optical taper, alignment is not as important.

A plurality of illumination fibers may be collected by mechanicalconnectors including, but not limited to, a metallic ring, a polymerring using glue or similar structures. After the fibers are boundtogether, the fibers may be cut in an even manner. The light fibers maybe polished smooth to assist in pointing light illumination. In anembodiment, the optical taper is mounted adjacent to a light fiberbundle with a tapered end that may be in contact with polished ends ofthe fibers.

One or more radiopaque markers may be placed on the catheter and/or theballoon. In an embodiment, the radiopaque marker is located at thetransition point between the proximal end of the balloon and the distalend of the catheter. The radiopaque marker, using radiopaque materialsuch as barium sulfate, tantalum, or other materials known to increaseradiopacity, allows the medical professional to view the distal end ofthe catheter using fluoroscopy techniques. The radiopaque materialprovides visibility during inflation to determine the precisepositioning of the balloon and/or catheter during placement andinflation. The radiopaque material permits visualization of voidscreated by air entrapped in the balloon. The radiopaque material permitsvisualization to preclude the balloon from misengaging or not meetingthe bone due to improper inflation to maintain a uniform balloon/boneinterface. Once the correct positioning of the balloon and/or catheteris determined, the proximal end of the catheter may be attached to acaulking gun type adhesive system that contains a bone reinforcingmixture.

One or more radiopaque markers on the proximal end and distal end of theballoon and/or catheter may be used to determine the position of theballoon and/or catheter within the bone to ensure correct location ofthe balloon through the use of an x-ray or fluoroscope. As the balloonis inflated, the multiple sections of bones are brought into a healingorientation and in a stable configuration. If the bone is in the healingorientation, illumination is provided via illumination fibers within theballoon and/or catheter. In an embodiment, a plurality of illuminationfibers are used to provide sufficient light to cure the reinforcingmaterial in the bone.

After the reinforcing material in the balloon is cured, such as by usingthe illumination fibers, an illumination band located, for example, atthe balloon/catheter junction may be activated causing light to cure theepoxy located in the catheter within the illumination band. Theillumination band is located adjacent to the proximal end of the balloonat the junction between the catheter and the balloon. The illuminationband extends around the catheter and has a stress concentrator. Thestress concentrator may be a notch, groove, channel or similar structurethat concentrates stress in the illumination band. The stressconcentrator of the illumination band may be notched, scored, indented,pre-weakened or pre-stressed to direct separation of the balloon fromthe catheter under specific torsional load. A delivery catheter may uselight guides composed of silica, silicon, or polymer materials thattransmit light of the proper frequency to the illumination band.

In an embodiment, the proximal end of the balloon may contain glue thatis hardened to form a separation area. The separation area ensures thatthere are no glue leaks from the catheter and/or the balloon. Theseparation area seals the catheter and/or balloon and removes thedelivery catheter by making a break at a known or predetermined site(e.g., a separation area). The separation area is located where thedistal end of the catheter meets the proximal end of the balloon becausethe glue in the balloon is hardened after activation of the illuminationband. The separation area may be various lengths and up to about an inchlong. When torque is applied to the catheter, the catheter separatesfrom the balloon. Twisting the catheter creates a torque sufficient inthe separation area to break the catheter from the balloon. The twistingcreates a sufficient shear to break the residual glue and create a cleanseparation of the catheter/balloon interface. Because the reinforcingmixture in the separation area has been cured and hardened by theillumination band, no reinforcing mixture can leak into the body fromthe catheter and/or the balloon.

For example, as shown in the embodiment depicted in FIG. 6, theillumination band 110 is connected to a light guide 136. The light guide136 may include a coating 138 surrounding a light guide transmissionarea 140. The light guide 136 may be removably attached to the catheter100 using balls 142 which mate with sockets 144. In an embodiment,safety measures prevent accidental or inadvertent illumination. Theillumination band is activated by a separate switch which is the activeprocess that the user takes to connect the light to be delivered. Havinga distinct switch to activate the illumination band may help to preventinadvertent delivery of light from the light source to cure thereinforcing material. In an embodiment, such as the embodiment depictedin FIG. 8, the illumination band 110 may have a switch which is asection 126 of the catheter that can be offset by lateral, vertical orhorizontal movement. When the section 126 is moved to an offsetposition, such as is depicted in FIG. 8, the illumination fibers 116move out of electrical connection with one another on either side of thesection 126 and the illumination band 110 is deactivated.

In an embodiment, such as the embodiment depicted in FIG. 9, the switchis a mating device 128 such as a rotating band or rotating fuse that isrotated to activate the illumination band causing illumination on thereinforcing material within the catheter to cure the area adjacent tothe illumination band. The mating device 128 may have differentconnectors 130, 132, such that when the mating device is rotated in afirst position, the electrical connectors 132 contact the illuminationfibers illuminating the illumination band and when the mating device isrotated, for example, by 90 degrees, into a second position, insulatingconnectors 130 contact illumination fibers preventing illumination ofthe illumination band. In an embodiment, such as the embodiment depictedin FIG. 10, the switch is a rotating fuse 134 that is rotated toilluminate the illumination band.

Once the illumination band is activated, a section of the infusioncatheter is sealed with the UV curable epoxy proximal and distal to theillumination band. The activation of the illumination band seals themost proximal end of the balloon, seals the distal end of the catheter,and ensures that there is a “hard seal” of the glue at the illuminationband allowing no glue to leak from the balloon or the catheter.

In an embodiment, the catheter is cut to separate the balloon from thecatheter. A device slides over the catheter and allows a right anglescissor to descend through the catheter and make a cut. The location ofthe cut may be determined by using a fluoroscope or an x-ray. In anembodiment, the cut location is at the terminal end of the introductionsite where the catheter meets the balloon.

In an embodiment, a fracture repair process reinforces a weakened orfractured bone without exposing the bone through a traditional surgicalincision (e.g., greater than about 10 mm). The presently disclosedembodiments use a minimally invasive approach by making a minor incisionto gain access. Minimally invasive refers to surgical means, such asmicrosurgical, endoscopic or arthroscopic surgical means, that can beaccomplished with minimal disruption of the pertinent musculature, forinstance, without the need for open access to the tissue injury site orthrough minimal incisions. Minimally invasive procedures are oftenaccomplished by the use of visualization such as fiber optic ormicroscopic visualization, and provide a post-operative recovery timethat is substantially less than the recovery time that accompanies thecorresponding open surgical approach.

Some of the presently disclosed embodiments are minimally invasive andminimize the cutting of surrounding tissue while implanting a bonefixator within the intramedullary cavity. By restoring and preservingbone structure, some of the presently disclosed embodiments permitadditional future treatment options. Benefits of minimally invasiveprocedures include causing less trauma because there is minimal bloodloss, a reduction in surgery and anesthetized time, shortenedhospitalization, and an easier and more rapid recovery.

In practice, an incision may be made at the proximal end or distal endof the fractured bone to reveal the bone surface. A medical professionalaccesses a bone. The medical professional makes an incision through theskin to expose the bone. Once the bone is exposed, it may be necessaryto retract some muscles and tissues that may be in view of the bone.Penetration through the compact layer (cortical bone), the spongy layer(cancellous bone) and a portion of the medullary cavity of the bone maybe accomplished by any method known in the art and be within the spiritand scope of the presently disclosed embodiments.

The access hole may be a minor drill hole with a diameter of about 3 mmto about 10 mm. A bone drill, awl or other medical device is used togain access through the compact layer, the spongy layer and a portion ofthe medullary cavity. The location of the bone penetration site may beat, proximal or distal to the location of the weakened or fracturedbone. In using a drill bit, it is desirable for the drill bit to beapplied at an angle other than 90° to the bone, for example, at an angleof about 20° to about 45°. The drill bit may be aimed toward the crackline of the weakened area in the bone.

As shown in the embodiments of FIG. 11 and FIGS. 14-16, a guidewire 150is introduced into the bone via the incision (not shown) and placedbetween the two sections 182, 184 of bone to cross a bone fracture 186.The guidewire 150 is delivered into the lumen 188 of the bone andcrosses the location of the break so that the guidewire 150 spansmultiple sections of bone 182, 184. After introducing the guidewire 150,a balloon portion 162, which is constructed and arranged to accommodatethe guidewire 150, is delivered over the guidewire 150 to the site ofthe fracture 186 and spans at least two sections 182, 184 of the bone.Once the balloon portion 162 is in place, the guidewire 150 may beremoved. In an embodiment, the balloon portion 162 may be introduced tothe surgical site by placing it within the confines of a flexible tube(not shown) and, in turn, delivering the flexible tube to the site ofthe fracture. By advancing the balloon catheter forward and pulling backon the flexible tube the balloon catheter may be exposed at the locationof the fracture. The balloon portion crosses a fracture in a minimallyinvasive manner.

As shown in the embodiment of FIG. 11, a balloon catheter 152 may be anoff-center tube balloon. The balloon catheter 152 may include aguidewire lumen 154 though which the guidewire 150 extends as well as aninfusional lumen 156 at least partially surrounded by balloon lightguides 158 and at least partially surrounded by illumination band lightguides 160. The illumination band light guides lead into an illuminationband 164. A balloon portion 164 of the balloon catheter 152 is locatedat a distal end of the balloon catheter 152. The balloon portion 164 mayinclude a lumen 166 through which the guidewire 150 or anotherinstrument may pass and radiopaque bands 168 at the most distal end sothat a surgeon or user may know the location of the tip of the ballooncatheter 152. In addition the balloon portion 164 may include a tubularballoon 170 and stents 172 encapsulated therein.

As shown in the embodiments of FIGS. 17-19, a balloon portion 162 isintroduced into the bone via the incision (not shown) and placed betweentwo sections 182, 184 of bone to cross the bone fracture 186. Theballoon portion 162 is delivered into the lumen 188 of the bone andcrosses the location of the break so that the balloon portion 162 spansmultiple sections of bone 182, 184. The location of the balloon portionmay be determined using a marker which are detectable from the outsideor the inside of the bone. For example, as shown in the embodimentdepicted in FIG. 18, radiopaque markers 190, which are visible fromoutside of the body using x-ray or other detection means, are located onthe distal and proximal ends of the balloon portion 162 to help alignand position the balloon portion 162. After introduction to the bone,the balloon portion 162 is manipulated to span at least two sections182, 184 of the bone. Once the balloon portion 162 is in place, theballoon portion 162 is inflated, for example by filling the balloon witha UV cured glue. As the balloon is inflated, the fracture 186 isreduced. Once orientation of the bone sections 182, 184 are confirmed tobe in a desired position, the glue may be fixed, such as by illuminationwith a UV emitting light source.

The balloon containing the hardened reinforcing mixture may be used asan internal support mandrel in the bone. Other devices (e.g., bonescrews, plates, pins, and similar devices) may be screwed into themandrel to provide support for compression and torsion of other devices.In an embodiment, the internal structure is used as a mandrel supportfor smaller pieces of a fracture repair since the mandrel allows screwsto be drilled into its hardened shape.

In an embodiment, an access hole of the bone is capable of accepting avariety of surgical instruments including, but not limited to,catheters, radial structural members, stents, stent-like devices,cannulas, orthopedic wires, stainless steel rods, metal pins and otherdevices. For example, a self-expandable device made from a material suchas Nitinol wire may be used to provide structure and support for a bonereinforcing mixture that is delivered to the balloon. A flexible tubemay be placed through the central hole and the self-expandable devicemay be collapsed and brought through the flexible tube and positionedwithin the balloon.

FIG. 12 and FIG. 13 show embodiments wherein a flexible tubular orregular balloon 174 has a radial structural member 176. The radialstructural member 176 is capable of being expanded within the confinesof the balloon and may be held and affixed within the UV curable glue.The radial structural member 176 provides for greater column support andstrength to the UV glue structure. In addition the catheters may have alumen 180 through which a guidewire 178 is inserted.

FIGS. 27-30 show various views of balloon catheter embodiments includinglevered radial structural members and plates. As shown in the embodimentof FIG. 27, Nitinol plates 232 sandwich connector wires 234therebetween. As shown in the embodiment of FIG. 28 a hinge wire 236moves in and out of radial structure members where a top Nitinol wire238 pushes and a bottom Nitinol wire 240 pulls. As shown in theembodiment of FIG. 29, a plate 242 has Nitinol wire attachments 244 anda hinge 246 therebetween. As shown in the embodiment of FIG. 30, uponactivation a frame 248 “swings” from a cylinder to an “I” beamconstruction having connector wires 250.

As shown in the embodiments depicted in FIG. 25 and FIG. 26, a radialstent embodiment includes a plurality of vanes 252 that openperpendicular to the outer diameter 254 once expanded. In a deflated(compressed) state, as shown in the embodiment of FIG. 25, the radialstent embodiment is with the vanes 252 lying flat along the wall of theballoon.

The radial structural embodiment includes a plurality of longitudinalplates that are oriented along the circumference and outer surface ofthe balloon prior to inflation of the balloon. The longitudinal platesare thin and metallic, and may be composed of a memory type metal. In anembodiment, the longitudinal plates are composed of Nitinol.

In a deflated (compressed) configuration, the plurality of longitudinalplates may be located at the distal end of the catheter within theballoon and wrapped around the inner catheter diameter. In thecompressed configuration, the plurality of longitudinal plates areadjacent to each other and may abut each other. In an embodiment, theplurality of longitudinal plates may overlap.

As the balloon is inflated, the stent is similarly expanded with theplurality of longitudinal plates moving outward and away from eachother. As the balloon continues to inflate, the diameter increases andthe orientation of the plurality of longitudinal plates move from beingparallel to the catheter, toward being perpendicular to the catheter.

The longitudinal plates of the structural member engage adjacent platesby a series of wires. The wires may be metallic, and may be composed ofa memory type metal. In an embodiment, the wires are composed ofNitinol. A lower portion of the plate located closest to the catheterwall engages the wire that is designed to contract, while an upperportion of the plate engages the wire that is designed to expand. Theopposing forces of the wires along with the radial expansion and theoverlapping layers of the plates cause a window blind effect where theradial structural member opens and becomes a rigid structure inside theballoon.

As shown in the embodiment of FIG. 20, a deflated balloon is placedwithin a medullary cavity 192 of a bone having a fracture 189. Theballoon catheter is inserted into the bone through a trocar fitting 193in a hole 195. The trocar fitting may be a high pressure trocar fittingwhich is installed in the access path. The trocar fitting may seal thechamber, may hold the glue in place prior to activation and may ensurethat air voids are removed from the cavity. The medullary cavity 192 mayalso contain a guidewire 194 for use in guiding and positioning aballoon 196. As shown in the embodiment of FIG. 21 the balloon 196 isinflated by filling the balloon 196 with bone cement. A syringe is usedto pack the balloon densely so it is hard upon activation by the lightsource. It is useful to note that high pressured delivery is notrequired to inflate the balloon or to move the glue from the gluedelivery system to the balloon. When using the syringe delivering theglue, no high pressure is used otherwise the balloon may deflate and theglue would retrograde. If the glue retrogrades, there is not enoughsuction to pull the administered glue from the balloon.

A balloon catheter may have a wide variety of properties including, butnot limited to, fiber type, fiber orientation, and resin matrix of thecomposite structure. As shown in FIG. 22, the balloon catheter 152 maybe inner reflective where a light reflective material 198 on an innersurface 200 of the balloon catheter enhances the reflective propertiesof light tubes.

The embodiment depicted in FIG. 23 shows a cross section view of aluminal fill having high modulus fiber structure. A bone 202 surroundsan outer surface 204 of the balloon portion 162. A lumen 206 of theballoon portion 162 is filled with a polymer 208. The balloon portion162 may also include an interlinked concentric ring of high modulusfiber 210. The embodiment depicted in FIG. 24 shows a cross section viewof an embodiment of an internal support structure of a balloon. Theballoon catheter may contain strong and stiff fibers used for carrying aload imposed on a composite while the resin matrix distributes the loadacross the fibers. An internal support within the balloon may helpcreate a composite filler that adds rigidity to the balloon and isuseful in application for longer bones where greater strength forfixation is desired. In particular, contained within the outer surface204 of the balloon are circumferential cross strut connectors 212, highwet modulus circumferential supports 214, lower ‘wet’ media 216, whichallows for some miscibility and outward compression, and high ‘wet’porous high modulus media 218.

In an embodiment, the catheter may be opaque. The opaque catheterensures that the glue is not activated by ambient light prior to thedesired activation of the light source. Similarly, a syringe may also beopaque to ensure that ambient light and operating room light does notactivate the glue prior to the desired activation time. In anembodiment, the glue is preloaded into the opaque syringe where inflowand outflow of the glue is regulated until application of the light isdesired to harden the glue.

After a balloon catheter is attached to the delivery system whichcontains the bone reinforcing mixture, the bone reinforcing mixture isinfused through one of the lumens of the balloon catheter. In anembodiment, the bone reinforcing mixture is a UV adhesive which requiresa UV light source to cure the adhesive. The balloon portion is theninflated and the UV adhesive is released through the plurality ofpassageways running along the sidewall of the balloon portion. The UVadhesive may also be released through the inner lumen of the catheter.The UV adhesive is pushed or compressed hydraulically up against thewall of the balloon. The light guides connected to the light source areilluminated which cures the UV adhesive. The balloon portion of thecatheter is then slightly deflated followed by infusion of the same or adifferent UV adhesive delivery system through a different lumen of theballoon catheter. The balloon portion is then re-inflated and the UVadhesive is released through passageways. The UV adhesive is pushed orcompressed hydraulically against the UV adhesive that has beenpreviously cured. The UV light guides connected to the light source areilluminated which cures the UV adhesive. The balloon portion of thecatheter is then slightly deflated followed by infusion of the same or adifferent UV adhesive delivery system through a different lumen of theballoon catheter. The balloon is being reinforced from the walls inwardcreating a shell or layer by layer repair producing a strong, resilientunion. The process is repeated until most of the space in the balloonhas been filled with UV adhesive. A central space may remain in theballoon which may be filled in order to provide the strength and supportto the bone. An optical rod or similar device may be positioned in thecentral space and turned on or illuminated. An optical rod or similardevice can be made of fiber, silica, quartz, sapphire or similarmaterials. The UV light will then harden the remaining UV adhesive inthe balloon. The end of the optical rod may be cut and remain in theballoon to provide increased rigidity.

UV curing adhesives may use ultraviolet light to initiate curing, whichallows a bond without heating. Additives may be used with the UVadhesive delivery system, including, but not limited to drugs (forexample, antibiotics), proteins (for example, growth factors) or othernatural or synthetic additives.

An outer surface of the balloon may be coated with materials such asdrugs, bone glue, proteins, growth factors, or other coatings. Forexample, after a minimally invasive surgical procedure an infection maydevelop in the patient, requiring the patient to undergo antibiotictreatment. An antibiotic drug may be added to the outer surface of theballoon to prevent or combat a possible infection. Proteins, such as,for example, the bone morphogenic protein or other growth factors havebeen shown to induce the formation of cartilage and bone. A growthfactor may be added to the outer surface of the balloon to help inducethe formation of new bone. The lack of thermal egress with these gluesin the balloon maintains the effectiveness and stability of the coating.

In an embodiment, the outer surface of the balloon may have ribs,ridges, bumps or other shapes to help the balloon conform to the shapeof the cavity. Balloons may be constructed to achieve transit withinluminal cavities of bones and to expand, manipulate, and removeobstructions. In this way, the balloon may slide easier within theluminal bodies without coming in contact with surrounding tissue. Theballoon may also be designed to be placed in a bone and to grab afractured bone without any slippage using a textured surface with avariety of shapes such as small ridges or ribs.

In an embodiment, a water soluble glue is applied to the outer surfaceof the balloon. When the balloon is expanded and engages the moist bone,the water soluble glue on the outer surface of the balloon becomessticky or tacky and acts as a gripping member to increase the conformalbond of the balloon to the bone. Once the balloon is inflated, the outersurface of the balloon grips the bone forming a mechanical bond as wellas a chemical bond. These bonds prevent the potential for a boneslippage. It is useful to note that the water soluble glue may be curedby any light (e.g., UV not required).

In an embodiment, a textured surface may provide one or more ridges thatallow grabbing both portions of the bone segments. In an embodiment,ridges are circumferential to the balloon and designed to add more grabto the inflated balloon on contact with the bone. The ridges are alsocompressive so the ridges fold up on the bone when the balloon iscompletely inflated. In an embodiment, sand blasted surfacing on theouter surface of the balloon improves the connection and adhesionbetween the outer surface of the balloon and the inner bone. Thesurfacing significantly increases the amount of surface area that comesin contact with the bone resulting in a stronger grip.

A two wall balloon has an inner wall and an outer wall making a tube. Aradial structural member may be placed inside the tube. A radialstructural member is inside the balloon and the epoxy expands theballoon. Then simultaneous with the expansion the radial structuralmember is being expanded.

In an embodiment, a longer radial structural member extends beyond thedistal and proximal ends of the balloon within the intramedullarycavity. When the balloon is expanded, the radial structural membersupports beyond and farther than the actual area of the balloon, and theradial structural member provides greater strength to the bone,resulting in a stronger device using a small balloon. Typically, radialstructural members are constructed from non-thrombogenic materials ofsufficient flexibility (in an unexpanded state) to allow passage throughguiding catheters and tortuous vessels. Such radial structural membersare typically radiopaque to allow fluoroscopic visualization. Radialstructural members may be constructed from stainless steel or titanium,e.g., in the form of an expandable mesh, wire coil, slotted tube, orzigzag design.

In an embodiment, an injectable fixation pin engages a cavity of thebone completely around the intramedullary cavity of the bone. Theinternal fixation pin is capable of holding and affixing the bone, whichremoves the need for external casting. A benefit of the internalfixation pin is that bone-on-bone rubbing or chatter at the fracturesite is reduced which enhances healing by having about 360 degree radialcontact with evenly distributed pressures with the bone over the lengthof the internal fixation pin. The internal fixation pin securely affixesthe bone fragments and minimizes flexure to hold the bone in place. Theinternal fixation pin is placed within the intramedullary cavity of thebone without a driving force prior to inflation.

In an embodiment, a small access is created in the bone. In bones withmarrow, a section of the marrow should be cleared providing access tothe cortical bone. Clearing the marrow results in good approximation andforce on bone fragments. Next a balloon is inserted. In an embodiment,the balloon is delivered using the force of the catheter to insert theballoon to span the fracture. In an embodiment, a guidewire is deliveredto the fracture site and the balloon is delivered over the guidewire tothe fracture site. In an embodiment, a balloon is placed in a flexibledelivery tube and the balloon and the delivery tube is sent to thefracture site and then the delivery tube is withdrawn, exposing theballoon. In an embodiment, the delivery balloon could be an expandableframework that the balloon uses to expand like that of a molly bolt. Amolly bolt could be placed on a flexible rod and the balloon is used toexpand the molly bolt resulting in additional structural support.

The balloon is inflated when a UV curable, light activated epoxy isinfused through a catheter to the balloon. In an embodiment, the balloonis constructed out of a polyethylene terephthalate (PET) nylon aramet orother non-consumable materials. PET is a thermoplastic polymer resin ofthe polyester family that is used in synthetic fibers. Depending on itsprocessing and thermal history, PET may exist both as an amorphous andas a semi-crystalline material. Semi-crystalline PET has good strength,ductility, stiffness and hardness. Amorphous PET has better ductility,but less stiffness and hardness. PET can be semi-rigid to rigid,depending on its thickness, and is very lightweight. PET is strong andimpact-resistant, naturally colorless and transparent and has goodresistance to mineral oils, solvents and acids, but not to bases.

The balloon typically does not have any valves. One benefit of having novalves is that the balloon may be inflated or deflated as much asnecessary to assist in the fracture reduction and placement. Anotherbenefit of the balloon having no valves is the efficacy and safety ofthe device. When there is a separation of epoxies prior to curing, thereis a potential for particles to egress. Since, since there is nocommunication passage of glue to the body there cannot be any leakage ofepoxy because all the glue is contained within the balloon. In anembodiment, a permanent seal is created between an implant that is bothhardened and affixed prior to the delivery catheter being removed. Theballoon may have valves, as all of the embodiments are not intended tobe limited in this manner.

In an embodiment, a double wall balloon is used. A double wall balloonis a balloon within a balloon that protects against a rupture of theinner balloon and also keeps the hardened glue mixture from the bloodstream. As the outer balloon comes in contact with the rough and surfaceof the bone, the inner balloon remains in contact with the smoothsurface of the polyethylene terephthalate (PET) inner material. Eachballoon may be inflated in turn until the desired structure is obtained.Any unused balloons may remain deflated with the cavity of the otherinflated balloons. A balloon within a balloon may also allow for preciseglue location since there is a variable durometer.

In an embodiment, multiple balloons are inserted together with multiplelumens and at least one inflation lumen for each balloon. The innermostballoon would be infused first and could be infused with the strongestglue having the highest shore or durometer. After the inner balloon ishardened, the next balloon is infused with a glue which may have avariable shore or durometer or the same shore or durometer and thenhardened. The process is continued until the lumen is completely filled.If there are extra balloons, they would engage the inner balloons andpush against the outer cavity of the balloon. The balloons would stillconform to the shape of the bone cavity. In an embodiment, the outerlayer could have a lower shore or durometer (i.e. be softer) and providea shock absorber approach to absorb any pressure impact along the boneinterface.

In an embodiment, the inflatable balloon is encapsulated in anexpandable metallic tube. The metallic tube may be designed to extendbeyond the area of the fracture into a healthy bone. The metallic tubemay have up to four or more pre-formed lengths that make up the tube.The tube may be capable of being split and provide a greaterlongitudinal strength than that of the balloon length. The tube that iscontemplated could have some ridges or serrations on the outer surfaceto engage the bone and grab the surface as it is compressed against thebone to prevent any shifting.

The presently disclosed embodiments can be used to treat a wristfracture of a radius, an ulna or other wrist and hand bones, resultingin a wrist reduction. The wrist is a collection of many joints and bonesthat allow use of the hands. The wrist has to be mobile while providingthe strength for gripping. The wrist comprises at least eight separatesmall bones called the carpal bones, which connect the two bones of theforearm, called the radius and the ulna, to the bones of the hand andfingers. The metacarpal bones are the long bones that lie mostlyunderneath the palm, and they are in turn attached to the phalanges, thebones in the fingers and thumb. The wrist is complicated because everysmall bone forms a joint with its neighbor. Ligaments connect all thesmall bones to each other, and to the radius, ulna, and metacarpalbones. A wrist injury, such as falling on the outstretched hand, candamage these ligaments and change the way the bones of the wrist worktogether. The wrist can be injured in numerous ways. Some injuries seemto be no more than a simple sprain of the wrist when the injury occurs,but problems can develop years later. The joints are covered witharticular cartilage that cushions the joints. A more serious injury,such as a fracture of one or more bones of the wrist, can injure thearticular cartilage surfaces of the joints and lead to degenerativearthritis.

Distal radius fractures are common injuries that occur at the distal endof the wrist, where the wrist joint lies. The most common form of wristfracture causes the radius to bend away from the palm. There may be achange in shape of the wrist, which is called the “dinner fork”deformity after its shape.

The most common cause of wrist fractures is when an individual falls onan outstretched hand. In young adults, fracture is the result ofmoderate to severe force. The risk of injury is increased in patientswith osteoporosis and other metabolic bone diseases. In addition, when afracture of the wrist occurs, the fracture may cause the radius tobecome short compared to the ulna. The ulna may then get caught when thewrist moves causing pain and restriction of movement.

The presently disclosed embodiments and methods treat a wrist fracturein a minimally invasive manner and can be used for a wrist reduction ofany of the bones of the wrist and hands, in particular the radius andulna.

The presently disclosed embodiments can be used to treat a claviclefracture, resulting in a clavicle reduction. The clavicle or collar boneis classified as a long bone that makes up part of the shoulder girdle(pectoral girdle). Present methods to affix a broken clavicle arelimited. The clavicle is located just below the surface of the skin, sothe potential for external fixation including plates and screws islimited. In addition, the lung and the subclavian artery reside belowthe collar bone so using screws is not an attractive option. Traditionaltreatment of clavicle fractures is to align the broken bone by puttingit in place, provide a sling for the arm and shoulder and pain relief,and to allow the bone to heal itself, monitoring progress with X-raysevery week or few weeks. There is no fixation, and the bone segmentsrejoin as callous formation and bone growth bring the fractured bonesegments together. During healing there is much motion at the fractureunion because there is not solid union and the callous formation oftenforms a discontinuity at the fracture site. A discontinuity in thecollar bone shape often results from a clavicle fracture.

The presently disclosed embodiments and methods treat a claviclefracture in a minimally invasive manner and can be used for a claviclereduction or collar bone reduction. A benefit of using a ballooncatheter to repair a collar bone is the repair minimizes post repairmisalignment of collar bone. A benefit of using the balloon catheter torepair a clavicle is to resolve the patient's pain during the healingprocess.

Those skilled in the art will recognize that the disclosed apparatus andmethods can be used for delivering reinforcing materials to other bones,such as radius, ulna, clavicle, metacarpals, phalanx, metatarsals,phalanges, tibia, fibula, humerus, spine, ribs, vertebrae, and otherbones and still be within the scope and spirit of the disclosedembodiments.

In an embodiment, a balloon catheter having larger sized ends of willcause the bone to be placed in inward compressive loading. The balloonis shaped so a proximal end and a distal end that have an inflateddiameter that is larger than a diameter of a middle portion of theballoon. The larger diameters of the balloon are toward the distal endand the proximal end that engage the bone beyond the fracture site. Theballoon shaped with larger diameters toward the proximal end and thedistal end drives the bone portions on each side of the fracturetogether. The balloon shaped with larger diameters toward the proximalend and the distal end tries to push the bone portions toward each otherto promote healing of the fracture.

In an embodiment, the balloon wall is composed of a plurality of layers.In an embodiment, the balloon wall has three layers so the balloon istri-layered. An outer layer of the balloon has at least a portion thatcan absorb moisture and expand, creating a thicker skin. In this mode ofloading, the upper skin of the balloon wall is in compression, the lowerskin of the balloon wall is in tension and the core layer of the balloonwall is subjected to shear stress. Thus, shear strength and stiffnessare important properties of a core layer of the balloon wall. To bendthe tri-layered balloon, one layer of the balloon wall is compressed,another layer of the balloon wall is placed in tension, and the corelayer of the balloon wall is subjected to shear stress.

In an embodiment, a sound may be used to clear the cavity of the bone ofany extraneous material to ensure a conforming fit between the balloonand the cavity, knocking off spicules. In an embodiment, a stent couldbe attached to the sound and is inserted through the cavity. The stentwould remain within the cavity to support the cavity. The balloon wouldthen be placed into the cavity after the stent has already been placedthere. In an embodiment, a radial structural member may be locatedinside a balloon.

For bones with marrow, the medullary material should be cleared from themedullary cavity prior to insertion of the balloon catheter. Marrow isfound mainly in the flat bones such as hip bone, breast bone, skull,ribs, vertebrae and shoulder blades, and in the cancellous material atthe proximal ends of the long bones like the femur and humerus. Once themedullary cavity is reached, the medullary material including air,blood, fluids, fat, marrow, tissue and bone debris needs to be removedto form a void. The void is defined as a hollowed out space, wherein afirst position defines the most distal edge of the void with relation tothe penetration point on the bone, and a second position defines themost proximal edge of the void with relation to the penetration site onthe bone. The bone may be hollowed out sufficiently to have themedullary material of the medullary cavity up to the cortical boneremoved. The length of medullary material removed will vary according tothe area of weakened portion, but will typically include about 3 cmabove and about 3 cm below the weakened portion of the bone. There aremany methods for removing the medullary material that are known in theart and within the spirit and scope on the presently disclosedembodiments. Methods include those described in U.S. Pat. No. 4,294,251entitled “Method of Suction Lavage,” U.S. Pat. No. 5,554,111 entitled“Bone Cleaning and Drying system,” U.S. Pat. No. 5,707,374 entitled“Apparatus for Preparing the Medullary Cavity,” U.S. Pat. No. 6,478,751entitled “Bone Marrow Aspiration Needle,” and U.S. Pat. No. 6,358,252entitled “Apparatus for Extracting Bone Marrow.”

After the medullary material has been removed, the apparatus may bepositioned at the penetration site. A bone fitting portion is threadedinto the penetration site and the flexible tube is inserted through theinsertion hole of the bone fitting portion. In an embodiment, the lumenused may be smaller than the expanded diameter of the balloon. Theaccess hole need only to be large enough to be able to insert thediameter of the catheter with the deflated balloon around the catheter.For example, the introduction hole into the bone may have a diameter ofabout one millimeter to about three millimeters where the subsequentinflation of the balloon can be from about 20 millimeters up to about300 millimeters, as constrained by the internal diameter of the bone.This leaves results in a minimally invasive procedure to reduce the bonefracture. If desired, reinforcing materials including, but not limitedto, flexible orthopedic wires, stainless steel rods, and metal pins maybe added to the balloon before the flexible tube is placed in the bonefitting portion. The introduction of reinforcing materials to theballoon may help the bone reinforcing mixture to form a tight union,producing a structure that is strong and resilient.

In its expanded state, the internal fixation device is larger than theaccess hole that is created in the bone. By expanding from a deflatedstate to an inflated state in the medullary cavity, the internal fixatorprovides minimally invasive bone reduction. Inserting a balloon catheterwithin the medullary canal in a reduced diameter allows the ballooncatheter to adapt itself to the contours of the medullary canal.Fixation is achieved along the entire length of the balloon allowingproper positioning at fracture site. Other benefits include: a minimallyinvasive procedure, no interlocking wires/screws required, minimizedfluoroscopy exposure, reduced procedure time, one minimally invasiveentry point, thus reducing the risk of infection, as the balloon adaptsto the intramedullary canal shape and diameter, a homogeneous fixationof the fracture is achieved and there are no transverse movements at thefracture site, the balloon inflation will reduce the fracture fragmentsas there is an internal framework to push the fragments on, immediateaxial load transfer in-between the fracture fragments contributes tofaster callus formation. Using the presently disclosed embodiments, thebone reduction does not require any communicating devices in contactwith the skin, so there is less irritation and potential for infection.

In an embodiment, the reinforcing material is pre-formed into acustomized shape. A pre-determined shape or mold may be filled with thereinforcing material and the shaped material may be inserted into thebody. In an embodiment, the shaped material is further cured using oneof the processes described above, such as UV light curing. In anembodiment, the material is partially or completely cured while in themold and inserted into the body intact.

The devices and methods described herein may be used for a variety ofapplications, for example, they may be used to provide temporary supportto an external splint or to form a plate.

In an embodiment, light is delivered to a first end of the balloonthrough a first catheter and glue is delivered to the other end (e.g.,the second end) of the balloon through a second catheter. In anembodiment, both light and glue are delivered to the same end of theballoon and through separate catheters. In an embodiment, light and glueare delivered to the middle of the balloon through a single catheter.Light and glue may be delivered to the balloon through a single catheteror separate catheters, may be delivered to any location on the balloon(e.g., either end, middle or anywhere therebetween) and may be deliveredto the same or different locations as one another, as not all of thepresent embodiments are intended to be limited in these respects.

Advantages in treating osteoporotic bone and pathological fractures mayinclude minimal entry points which will reduce soft tissue injury andsubsequent adhesions and scar formation, benefits of adhesion, abilityto apply variable Durometer materials within the lumen capable ofchanging the characteristics of the epoxies to meet the needs andchallenges of the application, high tack and softer materials on theoutside of the lumen for bonding with the bone and “shock absorption” onthe outer layers and greater strength and rigidity on the inside.

Another advantage of using some of the presently disclosed embodimentsmay be that there is minimal soft tissue damage that occurs. Soft tissuedamage creates callous formations which are considered part of thenatural bone healing process. By minimizing the soft tissue damage,subsequent stiffness due to callous formations in and on the tendon isavoided. A small incision is made, through which the pin is driven intothe cavity of the bone resulting in good approximation and fixationwhile there is no need for a cast that is required with traditionalk-wire approach. The above identified advantages may result from some ofthe presently disclosed embodiments and not all embodiments necessarilyhave these advantages.

U.S. application Ser. No. 11/789,906 entitled “Apparatus and Methods forReinforcing Bone,” filed Apr. 26, 2007, is hereby incorporated herein byreference in its entirety.

All patents, patent applications, and published references cited hereinare hereby incorporated by reference in their entirety. It will beappreciated that several of the above-disclosed and other features andfunctions, or alternatives thereof, may be desirably combined into manyother different systems or applications. Various presently unforeseen orunanticipated alternatives, modifications, variations, or improvementstherein may be subsequently made by those skilled in the art which arealso intended to be encompassed by the following claims.

What is claimed is:
 1. An apparatus for delivering a reinforcing mixtureto a fractured bone of a wrist or a hand, resulting in a wristreduction, the apparatus comprising: a tube having a proximal end, adistal end, and a longitudinal axis therebetween, wherein the tube hasat least one inner lumen for passing a bone reinforcing mixturetherethrough; a balloon engaging the distal end of the tube, wherein theballoon expands from a substantially deflated state to a substantiallyinflated state upon the bone reinforcing mixture entering the balloon;at least one light guide extending through the tube into the balloon toguide a light into the balloon to cure the bone reinforcing mixture, anda switch coupled to the at least one light guide, the switch beingconfigured to control light guided by the light guide into the balloonto prevent inadvertent illumination of the bone reinforcing mixture,wherein the balloon, when in the inflated state by the bone reinforcingmixture in a cavity of the fractured bone, aligns bone fragments of thefractured bone.
 2. The apparatus of claim 1 further comprising a lightsource that provides light to the tube, the light source provides one ofan ultraviolet light to the tube or a visible light to the tube.
 3. Theapparatus of claim 1 wherein an outer surface of the balloon includes atextured surface, such that the textured surface includes one or moreshapes.
 4. The apparatus of claim 3 wherein the one or more shapes ofthe textured surface is one of ridges, ribs or both.
 5. The apparatus ofclaim 1 wherein an outer surface of the balloon includes bumps, suchthat the bumps are one of convex bumps, concave bumps or both.
 6. Theapparatus of claim 1 wherein an outer surface of the balloon is coatedwith one or more material, the material includes at least one of a drug,a bone glue, a protein such as a bone morphogenic protein or a growthfactor substance.
 7. The apparatus of claim 6 wherein the drug includesat least one of an infection preventative drug or an antibiotictreatment drug.
 8. The apparatus of claim 1 wherein the balloon isencapsulated in an expandable metallic tube, the expandable metallictube is capable of being split to provide a greater longitudinalstrength than that of a length of the balloon.
 9. The apparatus of claim8 wherein the expandable metallic tube extends beyond an area of thefractured bone and into a healthy bone.
 10. The apparatus of claim 1wherein the balloon includes an outer wall and an inner wall so as toform a tube.
 11. The apparatus of claim 10 further comprising a radialstructural member engaging the balloon.
 12. The apparatus of claim 11wherein the balloon inflates as the bone reinforcing mixture enters theballoon under pressure, while simultaneously expanding the radialstructural member inside the balloon.
 13. The apparatus of claim 1wherein the balloon includes a balloon wall that is composed of aplurality of layers.
 14. The apparatus of claim 13 wherein the pluralityof layers of the balloon wall include at least an outer layer, a corelayer and an inner layer.
 15. The apparatus of claim 14 wherein theouter layer having a first thickness, the outer layer includes at leasta portion that absorbs moisture and expands, so as to expand to a secondthickness.
 16. An apparatus for delivering a reinforcing mixture to afractured bone of a wrist or a hand, resulting in a wrist reduction, theapparatus comprising: a catheter having a proximal end, a distal end,and a longitudinal axis therebetween, wherein the catheter has at leastone inner lumen for passing a reinforcing mixture therethrough; aballoon extending from the distal end of the catheter, wherein theballoon begins to expand from a substantially deflated state to asubstantially inflated state as the reinforcing mixture enters theballoon, wherein the balloon expands to a shape so a proximal end and adistal end of the balloon have an inflated diameter that is larger thana diameter of a middle portion of the balloon; at least one light guideextending through the catheter into the balloon to guide a light intothe balloon to cure the reinforcing mixture; a light source coupled tothe at least one light guide and configured to deliver light to the atleast one light guide to cure the reinforcing mixture; a switch coupledto the at least one light guide, the switch being configured to controlthe light guided by the light guide into the balloon to preventinadvertent illumination of the bone reinforcing mixture; and a junctionconnecting the catheter to the balloon, wherein the junctionconcentrates stress applied to the catheter at the junction, wherein theballoon, when in the inflated state by the reinforcing mixture in acavity of the fractured bone, aligns bone fragments of the fracturedbone.
 17. The apparatus of claim 16 wherein the junction includes atleast one of a notch, a groove and a channel in the catheter, to form apre-weakened area extending substantially around a circumference of thecatheter, so as to separate the balloon from the catheter under at leasta predetermined load.
 18. The apparatus of claim 16 wherein the largerdiameter of the balloon toward the distal end and the proximal endengage the bone beyond an area of the fractured bone.
 19. A method forreinforcing a bone of a wrist or a hand comprising: penetrating the boneto gain access to a cavity in the bone; inserting a balloon engaging adistal end of a catheter into the cavity in the bone; infusing areinforcing mixture into the balloon through at least one lumen of thecatheter, wherein the balloon expands to a shape so a proximal end and adistal end of the balloon have an inflated diameter that is larger thana diameter of a middle portion of the balloon; activating a light sourceand delivering light from the light source to the balloon through atleast one light guide to harden the reinforcing mixture in the balloon;and controlling the light from the light source being delivered by thelight guide with a switch coupled to the light guide to preventinadvertent illumination of the reinforcing mixture.
 20. The method ofclaim 19 further comprising encapsulating the balloon in an expandablemetallic tube.
 21. The method of claim 20, wherein the expandablemetallic tube is capable of being split to provide a greaterlongitudinal strength than that of a length of the balloon.
 22. Themethod of claim 19, wherein the balloon includes an outer wall and aninner wall so as to form a tube.
 23. The method of claim 19 furthercomprising engaging the balloon with a radial structural member.
 24. Themethod of claim 19 further comprising expanding a radial structuremember while inflating the balloon as the bone reinforcing mixtureenters the balloon under pressure.